Building a new home or planning a major renovation is a big undertaking. Between coordinating everything with the builders and having your space turned inside out, you may have forgotten about one of your landscape’s most valuable assets: existing trees. Construction vehicles and machinery can easily damage them, and that’s why trees should be protected. An injured tree can become prone to disease or experience other health problems that lead to its demise. Learn the steps to protect your trees during construction, so they’ll stay healthy and beautiful for years to come.
1. Identify mature trees that are vulnerable to construction.
This includes trees that are near the renovation area and ones within the path of construction vehicles. It’s wise to plan a route through the property in consultation with your builder. This puts everyone on the same page and lets your lead contractor know that the trees are important to you and that you want them preserved. A specific route for vehicle access also helps plan a coordinated construction site.
Your builder or lead contractor will be responsible for staging this route as part of the construction process. Speak up early about the need to protect mature trees on your property. In sites with limited access or tight spaces, there are technologies and methods that can limit disturbance around protected trees.
2. Review local ordinances designed to protect trees during construction.
Some municipalities have strict requirements for the type of fence and identifying signage that can be used. Others have no regulations, leaving it up to the homeowner to protect existing trees.
Also note if there are trees that must be protected in your property’s adjacent public right of way. A local ordinance often will protect street trees and trees within public easements. Know the locations of mature trees that may fall under your purview and know what regulations apply to them.
Shown: The orange plastic netting fence clearly marks a “do not disturb” zone around a mature tree.
3. Understand that trees can be harmed in a variety of ways but that injury is avoidable with proper planning.
There are three main tree components to protect:
- Roots: The roots can be damaged by soil compaction, a change in grade, trenching or other activity that cuts away significant portions of the roots. Know your tree’s critical root zone, an imaginary circle drawn on the ground in line with where the tree’s branches extend, based on the diameter of the trunk, and place your protective fence to surround it.
- Trunk and bark: Mechanical damage can occur if a vehicle or machinery impacts the trunk and strips away bark. This creates a wound that invites disease. At a minimum, protect the trunk by wrapping it with burlap or boards.
- Branches: Low branches can catch on vehicles and machinery too. This presents the same problem as the trunk getting hit: It creates a rough break in the branch, leaving the tree open to disease. Cut back any low branches that are in the path of construction vehicles.
Shown: A temporary chain-link fence provides a visual and physical barrier to limit disturbance around trees.
Photo by Richard Eriksson
4. Make a clear barrier.
This prevents heavy trucks and big machinery from driving close to the tree. A fence should clearly mark that it is protecting a tree so that the fence and the tree don’t get disturbed during construction. A general rule of thumb for correct placement of a tree protection fence or barrier is 1 foot away from the trunk for every inch of trunk diameter. For example, a tree with an 8-inch diameter — measured at chest height — would need a protection fence that circles around the tree with at least an 8-foot radius. The center of the circle is the trunk.
Shown: A required chain-link fence with clear signage safeguards a young oak tree planted in a public right of way between the sidewalk and street.
You should consult a professional if you need help with preserving and protecting mature trees. A certified arborist or a landscape architect can assist with surveying tree health, measuring trunk sizes and creating a tree protection plan for your trees during construction. A professional consultant is especially helpful if you have an expansive property, a mix of many tree species or a large number of mature trees. With the right planning, your trees will make it through the construction and continue to thrive.
via How to Protect Your Trees When You’re Remodeling or Building